Www.dragonlabs.eu is the place to shop for DOSD cases. 10g in weight. Static resistant and tested up to 55lbs of weight on any of the sides, not a single piece of damage . Black cases will be available soon (apologies for the delays mike, work have been slamming me recently).

First off what a fantastic product! I have it fitted in a 3m glider converted to electic using a pod, all home built.

The OSD just works straight out of the box, the Autopilot function I have working well after reading the manual and a little help from here. I can fly 'missions' and it works very well. Indeed last flight out my chineese VTX died and I got to watch a little dot go where it was supposed to go then come home all on it's own, even got comments that I could not have been controlling as it was far too smooth a flight (crabbing sidways into wind straight as you like towards me for 300 metres plus).

However I do have a problem getting the failsafe how I want it. My setup is using:

Futaba 7c 2.4 TX, Futaba 7 channel RX into the PPM encoder then into the DOSD. I am using two batteries, one connected directly to the DOSD and VTX and the other going to the ESC. Servos connected to the DOSD are the Rudder, Elevator, Ailerons (Y lead) and ESC. Futaba RX gets power from the PPM encoder connected to channel 3, this has data, power and ground connected. All other outputs from the RX just have data connected. I have set the end stops to get the 3 way switch on the TX to give OSD, Menu and Autopilot. This is how I have been using the autopilot.

To set failsafe I worked out if the PPM frequency was too high the DOSD will 'see' it as corrupt and activate failsafe. To do this I set the Futaba failsafe channel 3 (ESC) to 140% on loss of signal. This works everytime. The screen shows failsafe and Autopilot but I find the rudder and ailerons go left about 20% servo travel. I have video watching the autopilot trying to corirrect this.

As I say I have it working well using just the autopilot switch. I set failsafe and center servos in the air. I have set the whole thing up as if it was an old skyleader system I had. IE no electronic mixing, mechanical trims to centre as much as possible.

Anyone any idea on this one. I'm guessing it's the way I get the failsafe to work.

Mike, apologies for the delayed order. Work has been manic. Even worse. Over the last 3 weeks I've only had 1 flight (Dispite 2 visits to the flying field :P) which lasted all of 30 seconds before I realised I hadn't checked the battery in my quad. A hastey landing finally finished off the rubbish landing gear. But I havnt had a chance to design a better replacement, so the quad is grounded. So much to do :P.

Working in southampton tomorrow and the day after. A 6 hour round trip, twice on the trot after a 9 hour day on site :P. got 12 units done, just need a moment to myself to set the rest printing :P.

First off what a fantastic product! I have it fitted in a 3m glider converted to electic using a pod, all home built.

The OSD just works straight out of the box, the Autopilot function I have working well after reading the manual and a little help from here. I can fly 'missions' and it works very well. Indeed last flight out my chineese VTX died and I got to watch a little dot go where it was supposed to go then come home all on it's own, even got comments that I could not have been controlling as it was far too smooth a flight (crabbing sidways into wind straight as you like towards me for 300 metres plus).

However I do have a problem getting the failsafe how I want it. My setup is using:

Futaba 7c 2.4 TX, Futaba 7 channel RX into the PPM encoder then into the DOSD. I am using two batteries, one connected directly to the DOSD and VTX and the other going to the ESC. Servos connected to the DOSD are the Rudder, Elevator, Ailerons (Y lead) and ESC. Futaba RX gets power from the PPM encoder connected to channel 3, this has data, power and ground connected. All other outputs from the RX just have data connected. I have set the end stops to get the 3 way switch on the TX to give OSD, Menu and Autopilot. This is how I have been using the autopilot.

To set failsafe I worked out if the PPM frequency was too high the DOSD will 'see' it as corrupt and activate failsafe. To do this I set the Futaba failsafe channel 3 (ESC) to 140% on loss of signal. This works everytime. The screen shows failsafe and Autopilot but I find the rudder and ailerons go left about 20% servo travel. I have video watching the autopilot trying to corirrect this.

As I say I have it working well using just the autopilot switch. I set failsafe and center servos in the air. I have set the whole thing up as if it was an old skyleader system I had. IE no electronic mixing, mechanical trims to centre as much as possible.

Anyone any idea on this one. I'm guessing it's the way I get the failsafe to work.

Sorry lots of word to try and explain this.

Two things you can try. #1) Manually trim your control surfaces so the Tx requires no trim/sub-trim to fly straight and level. Then test what it does in failsafe. #2) Do step one first, then (while in straight and level flight) go into the DOSD menu and select 'Set Servo Neutrals'...or something like that...and try again. The DOSD seems to do best when there is little/no 'electronic' trim applied via your Tx.

Hi Forum,
To set failsafe I worked out if the PPM frequency was too high the DOSD will 'see' it as corrupt and activate failsafe. To do this I set the Futaba failsafe channel 3 (ESC) to 140% on loss of signal. This works everytime. The screen shows failsafe and Autopilot but I find the rudder and ailerons go left about 20% servo travel. I have video watching the autopilot trying to corirrect this.
.

You seem to have tapped into the OSD Failsafe rather than using the Rx Failsafe we all use. The DOSD was not programmed to work that way. It should have been. This is how many other OSD Failsafes work like ETOSD and RVOSD, and personally I consider it a major flaw of the DOSD. I'm actually very surprised you got it to failsafe using over throttle. I can't think of anything beyond Van's advice. Let us know if you figure it out and I will be switching my failsafe over to the over throttle method. You can then program a switch to give you 140% Throttle, and the RTH is always accessable instantly, even during waypoint tracking! This is how it should work.

Van: I pretty much have it mechanacally centred for trim. I have all the Futaba trims including the sub set to zero, with servo nutarals and failsafe set in the air. I dont understand why it works perfectly when I switch it to Autopilot but brings the servos off centre when autopilot is activated when it looses the PPM stream. Will let you know how I get on.

Iskess: Unfortunatly the only channel for this Futaba set is channel 3 and all you can do is set the throttle. I set the Futaba end stops to max (channel 3) then set this as the Futaba RX failsafe. Held on tight to the plane turned off the TX the DOSD will go straight into it's own failsafe every time with no hint of a throttle up. Works every time 100%. Not sure I should advocate this approach under saftey concerns, but I guess it would need to be a strange fault for the DOSD to pass on the PWM when it has no readable PPM to translate!

However I'm hoping I can get the DOSD to fly to 'home' position on radio failure. Almost there. Just need to work out why the DOSD gives 20% travel as soon as it is triggered into failsafe by the loss of the PPM signal.

I will try throttle max down approach to trigger the DOSD failsafe to see if this changes anything. Other than that I will look at somthing that will inject a 1.2ms to 1.6ms PPM to trigger the OSD autopilot as this works everytime. Has anyone considered using some kind of photo sensor on the bind LED of the futaba RX. I'm thinking along the lines of LED goes out then inject the PPM to get the DOSD into failsafe.

I know the real answer is get a Dragon link but their not legal here and transmit right across the UK radio ham frequency (70cm) which I have a licence for but the conditions state has to be a 'ground based' station. Too many HAMs here just sit and listen to scanners all day!

Thanks again for the responses I will carry on and let you know how it goes.

You seem to have tapped into the OSD Failsafe rather than using the Rx Failsafe we all use. The DOSD was not programmed to work that way. It should have been. This is how many other OSD Failsafes work like ETOSD and RVOSD, and personally I consider it a major flaw of the DOSD. I'm actually very surprised you got it to failsafe using over throttle. I can't think of anything beyond Van's advice. Let us know if you figure it out and I will be switching my failsafe over to the over throttle method. You can then program a switch to give you 140% Throttle, and the RTH is always accessable instantly, even during waypoint tracking! This is how it should work.

I don't think there's 'one best way' to trigger a failsafe that will fit everyone's needs and situation. I like the way the DOSD engages failsafe/RTH. I do wish there was a way to force a RTH while in Waypoint mode, but otherwise it works for me. The 'over-throttle' failsafe scenario would result in a full powered throttle (if you're not using the DOSD cruise control...like me...I prefer manual throttle control). I'd rather not have this situation. A no or low throttle would be safer (for anyone on the ground should the plane come crashing down) than one where full power was being applied. I can also think of instances where an 'over-throttle' failsafe would come in handy...like forcing a RTH condition while in a Waypoint mission. I think the DOSD still does a wonderful job for its size and age. It even does stuff that other systems can't/don't do yet.